Residential Security Solution: Gated Entry

A recent project came along during one of those droughts where after a while you begin to fear it will not ever rain again. Besides a poor economy in general, and a weak real estate market, locksmithing continues to be under siege from carpenters, handymen and DIY’ers, as well as Internet direct marketers & home improvement centers, to name just a few.

This project involved repairing and upgrading a residential vehicle gate for a young mother with small children, one of whom was diagnosed with autism, and who it was feared would leave the property if the gate was not adequately secured.

While it is generally impossible for a typical residence to be prepared to repel an attack at all times, physical security and electronic security are proven to help a lot. Best practices are to secure the property with a perimeter physical barrier, and start the security perimeter as far from the house as possible. An early enough warning and delaying the intruder buys time to contact police, find refuge or locate a weapon. A properly designed intrusion system notifies police of an intruder even if the homeowner is not there when the intruders pay a visit. Other threats and inconveniences a physical perimeter could address included solicitors and unleashed dogs in the neighborhood.

In addition to repairing the existing gate, the plan included:

Evaluating/repairing/replacing the existing gate operator

Adding an electromagnetic lock

Providing wireless controls for the operator

Installing a gate position lock status monitor

Providing a PTZ camera

Upgrading outdoor lighting.

The gate operator controller was housed in a hollow wooden gate post which was leaking like a sieve and also offering no protection against insects. So the gate controller was covered in dirt, sand and insects. Two 12 V 8AH gel batteries which had been previously connected were dead.

The power transformer terminals were rusty but the transformer was putting out 18 Volts. An electrical receptacle was live but disassembled and looked like it deserved to be dead and buried. When I plugged in the transformer, the gate operator controller lit up and looked promising.

My plan of attack was to first repair the gate, then see if the gate controller and operator were able to swing the gate. Then I would add a lock to the gate, provide wireless controls to open the gate, and provide monitoring for the gate position.

The gate itself was an ill-conceived single arm about 13 feet long which was constructed with gate lumber. It was warped and not exactly swinging smoothly on undersized and damaged hinges.

Because of its excessive weight, the gate needed some additional support. I installed two gate wheels which helped take the pressure off the hinges.

Gate operators and controllers share many characteristics, so troubleshooting them adds to your cumulative knowledge on the topic. This particular operator used line voltage to drive the controller circuitry and a trickle charge for the batteries, but the operator arm itself was driven by the battery pack. This keeps the controller from requiring a massive power supply. In some applications, the system could be solar powered. The variables are the amount of sunlight available vs. the number of gate operations a day vs. the size of the solar collectors. Most of the solar powered systems I’ve encountered were problematical because the proper balance was not achieved.

The gate operator portion of the circuit had a 15 Amp fuse, and the old system was powered by a 16 AH battery array. I got some replacement batteries and performed a test.

The operator worked with the gate attached so we were able to implement the maglock and radio controls. The geometry of the gate necessitated a custom-fabricated aluminum bracket that would withstand the elements. I got exactly what I wanted at the right price from www.speedymetals.com.

Maglock

BEA’s 10GL1200R front-mounted and 10 GL1200SR side-mounted electromagnetic locks offer a conduit connection and 1200lb. holding force suitable for applications such as gates. BEA also offers a wide selection of brackets, making the lock suitable for many situations. The bond sensor and internal relock delay mean there are fewer additional parts to buy.

Receivers / Transmitters

For radio controls, I wanted the gate to be locked at all times and a radio control would be required to actuate the gate for normal entry and exits. An auxiliary control station would also be supplied so the gate system could be operated manually.

We wanted one radio control to be on a time zone, so the homeowner could control when that particular transmitter would function. An additional challenge: although line voltage was available to both gate posts, there were no interconnecting low voltage wiring, and the driveway was concrete so trenching would be difficult.

I designed a system using all wireless receivers and transmitters and a timer module. This was way less trouble than excavating the site.

Multiple applications (i.e. Vestibule) with Delay or No Delay programming

100 transmitters can be programmed into a single receiver

Removal of a single transmitter code

Up to 4 separate wireless Receivers can be activated by a single transmitter (i.e. 4-button FOB)

Red LED indicator confirms transmission and battery life

3-Volt or 9-Volt Battery Power

BEA 433MHz Series transmitters and receivers are ideal for the wireless activation and/or sequencing of automatic doors. A unique rolling code is transmitted each time the transmitter is activated (thus providing a secure signal).

Since receivers can be individually programmed, multiple receivers can be programmed differently, thus allowing for sequencing in multiple applications.

Those receivers programmed with NO DELAY will activate immediately upon receiving the transmitter signal. Those receivers programmed with a DELAY will activate at the end of their pre-determined time delay set by the potentiometer.

The use of multiple receivers will allow for the uninterrupted pace or hands-free operations through a pair of doors upon initial activation.

Event Timer

An event timer was used to control the single wireless fob which would be provided to individuals to whom it was not desired to grant 24-hour access. I wanted a timer with a friendly user interface so the homeowner could deal with normal operation and possible programming.

The ALTRONIX DPT724A is a versatile 24-hour, 365-day event timer designed to support a wide range of applications: Home and Building Automation, Security, Access Control, Lighting Control, Etc. The PT724A is equipped with an independently controlled form “C” relay contact that provides many latching and/or momentary operations during a program schedule of your choice. Events may be set for single or multiple operations on a daily and/or weekly schedule.

Input: 12 to 24 volts AC or DC operation

Relay: Form “C” relay contacts are rated 10 amp @120VAC/28VDC.

Standby current: 10mA (relay off) 50mA (relay on).

Features include:

EE Prom memory protects against loss of programming due to power failure.

Accurate crystal controlled clock.

Momentary and/or latching events.

Individually programmed daily/weekly events.

Block programming capacity can accommodate a total of 350 events per week.